Separate kernel and user switches into separate objects
Enable controller-less setups
Add more NOX options
Move TreeNet to new Mininet API
Also remove all non-object-oriented legacy Mininet code and updatetests.
User-space compatibility is untested, but most of the code for it isstill in.
Move Node functions into their own file
Nodes include Switch, Host, and Controller; move these to a separatefile.
This file still could use some attention to hide private functions.Node seems like a primary class to extend, for adding stuff like OpenvSwitch, so it could benefit from a simpler interface.